Routing and flow joint scheduling method and system based on link load peak value

Abstract

The invention discloses a route and flow joint scheduling method and system based on a link load peak value, and belongs to the field of time sensitive network flow scheduling research, and the method comprises the steps: modeling a target network as a directed graph, and defining a time trigger flow set; in combination with the idea of load balancing, a gating time slot allocation model of time-triggered traffic based on a joint routing scheduling and frame forwarding no-waiting mode is constructed in a mode that queuing is not allowed in frame forwarding; the method comprises the following steps: establishing a gating time slot allocation constraint of time-triggered traffic based on a joint routing scheduling and frame forwarding no-waiting mode, and constructing a joint scheduling problem by taking a minimum link load peak value in a network as a scheduling target; and calling a joint routing joint scheduling algorithm based on a link load peak value, and determining a scheduling scheme of the time-triggered traffic. Transmission waiting caused by queue queuing and resource competition in a traditional scheduling method is avoided; and meanwhile, the high load of part of links caused by time-triggered stream transmission is reduced.

Description

Technical Field

[0001] The present invention belongs to the research field of time-sensitive network traffic scheduling, and in particular relates to a method and system for jointly scheduling routing and traffic based on link load peak value. Background Art

[0002] Time-sensitive networking is a series of standards developed by the IEEE 802.1 working group to provide deterministic and low-latency communication services over Ethernet. Time-sensitive networking technology has broad application prospects in industrial automation, vehicle networks, and professional audio and video applications. In these application scenarios, the real-time and reliability requirements of data streams are extremely high. Therefore, how to efficiently schedule data streams in the network to meet these strict latency requirements is an important research topic.

[0003] The existing time-sensitive network scheduling mechanisms mainly include priority-based and time-aware shaper-based scheduling methods. The priority-based scheduling method ensures that high-priority data flows are transmitted first by assigning different priorities to data flows, so as to reduce the transmission delay of key data flows. However, the priority-based scheduling method relies on the queuing mechanism of network devices, which easily leads to the accumulation of waiting and delay of data flows, and it is difficult to achieve wait-free transmission. The scheduling method based on time-aware shaper ensures that key data flows are transmitted within a specific time window through a pre-defined gating list, thereby ensuring the determinism and low latency of data flows. However, the existing scheduling methods use the shortest path transmission time to trigger the flow, or isolate the link state and routing, without considering the dynamic impact of the link state on the routing, resulting in excessive load on some links in the network, affecting the transmission of other types of traffic.

[0004] The current research work does not consider the wait-free transmission of time-triggered traffic and link load together, while the transmission of time-triggered traffic will inevitably lead to changes in link load. Therefore, a routing and traffic joint scheduling method based on link load peak is proposed. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a method and system for joint scheduling of routing and traffic based on link load peak value, which solves the problems in the prior art.

[0006] The purpose of the present invention can be achieved through the following technical solutions: The method for joint scheduling of routing and traffic based on link load peak value includes the following steps: Model the target network as a directed graph and define a set of time-triggered flows; Based on the time-triggered flow set, combined with the idea of ​​load balancing, in a way that frame forwarding does not allow queuing, from the perspective of traffic planning, a gated time slot allocation model for time-triggered traffic based on joint routing scheduling and frame forwarding without waiting is constructed; Establish a gating time slot allocation constraint for time-triggered traffic based on joint routing scheduling and frame forwarding without waiting, and construct a joint scheduling problem based on the gating time slot allocation model with minimizing the link load peak in the network as the scheduling goal; Based on the joint scheduling problem, a joint routing and joint scheduling algorithm based on link load peak is called to determine a scheduling scheme for time-triggered traffic.

[0007] Furthermore, the directed graph is ; Represents a collection of network nodes, consisting of a collection of terminal system nodes and switch node set composition; represents the set of links between adjacent network nodes, and Representation Node With Node A bidirectional link between The time-triggered flow set is , trigger flow at any time By , , , , , > Characterization, which represents the source node, destination node, size, cycle, generation time and deadline respectively.

[0008] Furthermore, the gated time slot allocation model for time-triggered traffic based on joint routing scheduling and frame forwarding without waiting is: in, Represents a time-triggered flow The end-to-end delay of Indicates that the route is a time-triggered flow Select the transmission path, Represents a time-triggered flow The propagation delay of Represents a time-triggered flow The processing delay, Indicates the clock synchronization delay; Represents a time-triggered flow The transmission delay of represents bandwidth, Represents a time-triggered flow size.

[0009] Further, the gating time slot allocation constraints of the time-triggered traffic based on the joint routing scheduling and frame forwarding no-wait mode include: frame constraints, frame transmission constraints, end-to-end constraints and link constraints; The frame constraints are: In the formula, express Any continuous link in express In the link The transmission start time on ; The frame transmission constraints are: in, represents the previous link in a continuous chain of links, represents the next link in the continuous link, express In the link The transmission start time on express In the link The transmission start time on ; The end-to-end constraints are: in, Represents a time-triggered flow Deadline: The link constraints are: in, represents a super cycle, Represents a time-triggered flow The index value of the number of transmissions in the super period, Represents a time-triggered flow The index value of the number of transmissions in the super period.

[0010] Furthermore, the joint scheduling problem is: in, Indicates the link load peak value, Indicates the link load, Represents a time-triggered flow In the link If the time-triggered flow Not passing , the value is 0.

[0011] Furthermore, the step of determining a time-triggered traffic scheduling scheme includes: S401, input network topology , time-triggered flow set ; S402, defining a link time slot allocation table, a link load table, a transmission start time table, and a routing entry table, and the initial values ​​are all empty sets; S403, traversing time trigger flow set Each time-triggered stream in , use depth-first traversal to calculate the time trigger flow A set of paths; S404, using the least common multiple method to calculate the time-triggered flow set The super cycle ; S405, time-triggered flow set The flows in are sorted in non-decreasing order according to the size of the supercycle; S406, traversing time trigger flow set Each time-triggered stream in , if the flow set traversal is completed, go to S416, otherwise go to S407; S407, traversal time trigger flow By comparing the link load peak of each path, find the path set with the smallest link load peak and sort them in non-decreasing order by path length; S408, traverse each path in the path set with the smallest link load peak value , if the path traversal is completed, go to S412, otherwise go to S409; S409, calculation time trigger flow In no-wait mode End-to-end delay as a transmission path ,if Exceeded time trigger flow Deadline , then enter S408 for the next cycle, otherwise enter S410; S410, calling the earliest transmission start time calculation algorithm to calculate the time trigger flow In no-wait mode The transmission start time when used as a transmission path ; If the earliest transmission start time is found, that is , then enter S411; otherwise enter S408 for the next cycle; S411, update time trigger flow The transfer start time and the optimal path , when one is found, the path traversal is terminated and the process goes to S412; S412, if the earliest transmission start time is found, that is , go to S413, otherwise go to S415; S413, updating the link time slot allocation table hop by hop and cycle by cycle, and reordering the allocated time slots on the affected links in ascending order according to the transmission start time, and updating the link load table at the same time, and entering S414; S414, update the transmission start schedule and routing entry table, and enter S406 for the next cycle; S415, clear the link time slot allocation table, the transmission start time table and the routing entry table, and enter S416; S416, returning the link time slot allocation table, the transmission start time table and the routing entry table.

[0012] The routing and traffic joint scheduling system based on link load peak includes: Flow set building module: Model the target network as a directed graph and define time-triggered flow sets; Time slot allocation model construction module: Based on the time-triggered flow set, combined with the idea of ​​load balancing, and in a way that frame forwarding does not allow queuing, from the perspective of traffic planning, a gated time slot allocation model for time-triggered traffic based on joint routing scheduling and frame forwarding without waiting is constructed; Scheduling problem construction module: establishes the gating time slot allocation constraints of time-triggered traffic based on joint routing scheduling and frame forwarding without waiting, and constructs the joint scheduling problem based on the gating time slot allocation model with minimizing the link load peak in the network as the scheduling goal; And, a scheduling scheme determination module: based on the joint scheduling problem, calling a joint routing and joint scheduling algorithm based on link load peak value to determine a scheduling scheme for time-triggered traffic.

[0013] A computer storage medium stores a readable program, which can execute the above-mentioned routing and traffic joint scheduling method based on link load peak when the program is running.

[0014] An electronic device, comprising: a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other through the communication bus; The memory is used to store at least one executable instruction, and the executable instruction enables the processor to perform operations corresponding to the above-mentioned routing and traffic joint scheduling method based on link load peak value.

[0015] A computer program product includes computer instructions, wherein the computer instructions instruct a computing device to execute operations corresponding to the above-mentioned link load peak-based routing and traffic joint scheduling method.

[0016] Beneficial effects of the present invention: The present invention aims at the scheduling problem of time-triggered traffic in a time-sensitive network and provides a routing and traffic joint scheduling method based on link load peak in a time-sensitive network. The method aims to minimize the link load peak in the network, realizes true wait-free transmission, avoids the transmission waiting caused by queue queuing and resource competition in traditional scheduling methods, thereby ensuring bounded delay and jitter of time-triggered traffic; at the same time, it reduces the high load of some links caused by time-triggered flow transmission, and reduces the impact on the transmission of other types of traffic. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 It is a flow chart of the routing and traffic joint scheduling method based on link load peak value of the present invention; Figure 2 is a flow chart of the joint scheduling algorithm of the present invention; Figure 3 is a flow chart of calculating the earliest transmission start time of the present invention; Figure 4 is a network topology diagram of the joint scheduling method in Embodiment 2 of the present invention; Figure 5 This is an example diagram of time slot allocation in fixed route scheduling and no-waiting mode in Embodiment 2 of the present invention; Figure 6 This is an example diagram of time slot allocation in the joint routing scheduling and no-wait mode in Embodiment 2 of the present invention; Figure 7 is a network topology scenario diagram of the joint scheduling method in Embodiment 3 of the present invention; Figure 8 is a comparison diagram of link load peaks of the joint scheduling method in Embodiment 3 of the present invention; Fig. 9 is a comparison chart of average scheduling rates of the joint scheduling method in Example 3 of the present invention; Fig.10 This is a comparison chart of the execution time of the joint scheduling method in Example 3 of the present invention. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Example 1 like Figure 1 As shown, in a time-sensitive network, a routing and traffic joint scheduling method based on link load peak value includes the following steps: S1, model the target network as a directed graph and define the time-triggered flow set ; Model the target network as a directed graph ; Represents a collection of network nodes, consisting of a collection of terminal system nodes and a collection of switch nodes that comply with the IEEE 802.1Qbv standard Composition, then there are ; represents the set of links between adjacent network nodes, and Representation Node With Node A bidirectional link between For time-triggered flow sets in scheduling tasks , trigger flow at any time By tuple< , , , , , > Characterization, which represents the source node, destination node, size, period, generation time and deadline respectively. Time-sensitive networking works at the second layer of the network. The time-triggered flow that exceeds the maximum transmission unit size is split into a set of frames for continuous transmission.

[0021] S2, based on the time-triggered flow set defined in S1, combined with the idea of ​​load balancing, and in a way that frame forwarding does not allow queuing, from the perspective of traffic planning, builds a gated time slot allocation model for time-triggered traffic based on joint routing scheduling and frame forwarding without waiting; The end-to-end delay of a frame is defined as the time from when the source node releases the frame to when the destination node receives the frame. This delay consists of four parts: propagation delay, processing delay, queuing delay, and transmission delay. The transmission delay It can be expressed as: (1) in, Indicates bandwidth, time-triggered flow End-to-end delay It can be expressed as: (2) in, Indicates that the route is a time-triggered flow Select the transmission path, Represents a time-triggered flow The propagation delay of Represents a time-triggered flow The processing delay, Indicates the clock synchronization delay. express The link on Represents a time-triggered flow exist The queuing delay; The no-wait mode requires continuous transmission of frames along the path, that is, no queuing is allowed when forwarding frames, and the queuing delay is zero. The end-to-end delay is: (3) S3, establishes the gated time slot allocation constraints for time-triggered traffic based on joint routing scheduling and frame forwarding without waiting, and based on the gated time slot allocation model constructed in S2, takes minimizing the link load peak in the network as the scheduling goal, and formalizes the joint scheduling problem; Gated time slot allocation constraints for time-triggered traffic based on joint routing scheduling and frame forwarding without waiting, including: frame constraints, frame transmission constraints, end-to-end constraints, and link constraints; 1) Establish frame constraints The frame constraint requires that the transmission start time of a frame on the link it passes through is non-negative, and the transmission must be completed within its period; (4) In the formula, express Any continuous link in express In the link The transmission start time on ; 2) Establish frame transmission constraints The frame transmission constraint requires that the transmission start time of the same frame on the successor link must be greater than or equal to the transmission completion time on the predecessor link; (5) in, represents the previous link in a continuous chain of links, represents the next link in the continuous link, Represents a time-triggered flow In the link The transmission start time on Represents a time-triggered flow In the link The transmission start time on ; 3) Establish end-to-end constraints The end-to-end constraint requires that the time interval between the time when any frame arrives at the receiving end and the time when it is sent from the sending end must be less than or equal to the deadline. ; (6) in, Represents a time-triggered flow Deadline: 4) Establish link constraints Link constraints require that any two frames on the same link trigger the flow and There is no overlap in time. For a super period, this constraint can be converted into any two frames on the same link, where the transmission start time of one frame must be greater than or equal to the transmission end time of the other frame; (7) in, represents a super cycle, Represents a time-triggered flow The index value of the number of transmissions in the super period, Represents a time-triggered flow The index value of the number of transmissions in the super period; Link Load It refers to the ratio of the sum of the transmission times of all time-triggered flows passing through a single link in one supercycle to the supercycle, which can be expressed as: (8) in, Represents a time-triggered flow In the link If the time-triggered flow No link , then the value is 0; Link load peak It refers to the maximum value of all link loads in the network in one super cycle, which can be expressed as: (9) Based on the common constraints of (4), (5), (6), and (7), minimizing the peak load of the links in the network is taken as the scheduling objective. The formalized joint scheduling problem is expressed as: (10) S4, based on the joint scheduling problem formed in S3, calls the joint routing and joint scheduling algorithm based on the link load peak to determine the scheduling scheme for time-triggered traffic; like Figure 2 As shown, the specific steps of calling the joint routing and joint scheduling algorithm based on the link load peak value and determining the scheduling scheme of the time-triggered traffic are as follows: S401, input network topology , time-triggered flow set ; S402, define a link time slot allocation table, the initial value of which is an empty set, for recording the allocated time slots of each link; define a link load table, the initial value of which is an empty set, for recording the load of each link; define a transmission start time table, the initial value of which is an empty set, for recording the transmission start time of the scheduled flow; define a routing entry table, the initial value of which is an empty set, for recording the optimal path of the scheduled flow; S403, traversing time trigger flow set Each time-triggered stream in , use depth-first traversal to calculate the time trigger flow A collection of simple paths; S404, using the least common multiple method to calculate the time-triggered flow set The super cycle ; S405, time-triggered flow set The flows in are sorted in non-decreasing order according to the size of the supercycle, which can be expressed as ; S406, traverse Each time-triggered stream in , if the flow set traversal is completed, go to S416, otherwise go to S407; S407, traversal time trigger flow By comparing the link load peak of each path, find the path set with the smallest link load peak , and sorted in non-decreasing order by path length; S408, traverse the path set with the smallest link load peak Each path in , if the path traversal is completed, go to S412, otherwise go to S409; S409, calculation time trigger flow In no-wait mode End-to-end delay as a transmission path ,if Exceeded time trigger flow Deadline , then enter S408 for the next cycle, otherwise enter S410; S410, calling the earliest transmission start time calculation algorithm to calculate the time trigger flow In no-wait mode The transmission start time when used as a transmission path ; If the earliest transmission start time is found, that is , then enter S411; otherwise enter S408 for the next cycle; S411, update time trigger flow The transfer start time and the optimal path , when one is found, the path traversal is terminated and the process goes to S412; S412, if the earliest transmission start time is found, that is , go to S413, otherwise go to S415; S413, updating the link time slot allocation table hop by hop and cycle by cycle, and reordering the allocated time slots on the affected link in ascending order according to the transmission start time to improve the subsequent detection efficiency of the available time slots on the link, and updating the link load table at the same time, and entering S414; S414, update the transmission start schedule and routing entry table, and enter S406 for the next cycle; S415, clear the link time slot allocation table, the transmission start time table and the routing entry table, and enter S416; S416, returning the link time slot allocation table, the transmission start time table and the routing entry table.

[0022] like Figure 3 As shown, in S410, the earliest transmission start time calculation algorithm includes the following specific steps: Step 1: Enter the time to trigger the flow , transmission path ; Step 2: Define the time interval as ,in Represents a time-triggered flow The latest transmission start time in no-wait mode; Indicates the transmission end time of the previous hop of the time-triggered flow currently being calculated during the time interval traversal process; the time slot interval is defined as ,in Indicates the start time of the time slot interval, Indicates the end time of the time slot interval; Represents a time-triggered flow The index value of the number of transmissions in the super period; Step 3: Calculate the time to trigger the flow In no-wait mode End-to-end delay as a transmission path ; Step 4: Traverse the time values ​​in the time interval ,To ensure that the flow completes the transmission within its period, the frame constraint must be satisfied, that is, , otherwise let , go to step 10; Step 5, let As the transmission start time of the next hop of the time-triggered flow in the current calculation, to ensure that the transmission start time of the same frame on the successor link must be equal to the transmission completion time on the predecessor link, and the frame transmission constraint must be met; Step 6, traverse Each link in , if the link traversal is completed, go to step 10, otherwise go to step 7; Step 7, update the time slot interval to , the transmission start time of the next hop after the update is ; Step 8: Traverse the time trigger flow In each cycle of the super cycle, if the cycle traversal is completed, go to step 6 for the next cycle, otherwise go to step 9; Step 9, update the time slot interval to , determine whether the time slot interval is occupied link by link and cycle by cycle. If it is occupied, let Go to step 4 for the next cycle, otherwise go to step 8 for the next cycle; Step 10: Return the earliest transmission start time .

[0023] Based on similar inventive concepts, an embodiment of the present invention further provides a computer storage medium storing a readable program, which can execute the above-mentioned routing and traffic joint scheduling method based on link load peak when the program is running.

[0024] Based on similar inventive concepts, an embodiment of the present invention provides an electronic device, comprising: a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other through the communication bus; The memory is used to store at least one executable instruction, and the executable instruction enables the processor to perform operations corresponding to the above-mentioned routing and traffic joint scheduling method based on link load peak value.

[0025] Based on similar inventive concepts, an embodiment of the present invention further provides a computer program product, including computer instructions, which instruct a computing device to execute operations corresponding to the above-mentioned routing and traffic joint scheduling method based on link load peak.

[0026] Example 2 In order to verify and illustrate the technical effects adopted in the method for joint scheduling of routing and traffic based on link load peak of the present invention, this embodiment tests the time slot allocation instance under fixed routing scheduling and no-waiting mode and the time slot allocation instance under joint routing scheduling and no-waiting mode in the present invention respectively.

[0027] Network topology such as Figure 4 As shown in the figure, assuming that the network bandwidth is 1Gbps, the propagation delay, processing delay and clock synchronization delay are all zero, and the scheduling task consists of 4 time-triggered flows. The attribute of the source node is , destination node , 250B, 100 ‌ ‌μs, 0, 100 ‌ ‌μs ‌>, time-triggered flow The attribute of the source node is , destination node ,250B,150‌‌μs,0,150‌‌μs ‌>,Time Triggered Flow The attribute of the source node is , destination node , 250B, 100 ‌ ‌μs, 0, 100 ‌ ‌μs ‌>, time-triggered flow The attribute of the source node is , destination node , 250B, 150 ‌ ‌μs, 0, 150 ‌ ‌μs ‌>, and schedule them one by one according to the order of traffic subscripts. represents a supercycle, then =300‌‌μs, the size of the four time-triggered flows is 250B. According to formula (1), the transmission delay of the four flows is 2‌‌μs.

[0028] Figure 5The example of time slot allocation under fixed routing scheduling and no waiting mode is shown. Since the shortest path transmission is adopted, the transmission path of the flow with the same source node and destination node is the same. Indicates the path , Indicates the path , Indicates the path , Indicates the path , Indicates the path , Indicates the path , assuming that from the source node To the destination node choose As the transmission path, from the source node To the destination node choose As a transmission path. Time-triggered flow and After the time slot allocation is completed, due to The time slot interval with a start time of 4 ‌ ‌ μs and an end time of 6 ‌ ‌ μs has been allocated to the time-triggered flow , in no-wait mode, the flow time triggers the flow exist The transmission start time on the The earliest transmission start time is delayed by 2 ‌ ‌μs. Time-triggered flow In summary, after the scheduling of the four time-triggered flows is completed, the network The link load is the highest, reaching 4.

[0029] Figure 6 The example of joint routing scheduling and time slot allocation in the no-wait mode is shown. The link load peak is used as the load balancing condition, and the time-triggered flow is used without considering the link load. There are 3 paths to choose from: , and At this time, the link load of each link is 0, so these three paths are time-triggered flows. The paths with the smallest link load peak are sorted in non-decreasing order by path length. As the transmission path, the earliest transmission start time is calculated first and it is found that it can be scheduled. The earliest transmission start time of is 0 ‌ ‌ μs, so the optimal path of the flow is The link time slot allocation table is updated with the earliest transmission start time calculated by the optimal path. There are 3 paths to choose from: , and ,at this time The cumulative link load is 1, which is , , , , , as well as These 7 links (composed of , and The maximum value of the load of all links in the network, so the time triggers the flow There are two paths with the smallest link load, and .because Compare Short length, As the transmission path, the earliest transmission start time is calculated first and it is found that it can be scheduled. The earliest transmission start time is 0 ‌ ‌ μs, so the time-triggered flow The optimal path is The link time slot allocation table is updated with the earliest transmission start time calculated by the optimal path. There are 3 paths to choose from: , and ,at this time , , The cumulative link loads of , , , , , as well as The maximum value of the load of these 7 links, so these 3 paths are time-triggered flows The paths with the smallest link load peak are sorted in non-decreasing order by path length. As the transmission path, the earliest transmission start time is calculated first and it is found that it can be scheduled. The earliest transmission start time is 1 ‌ ‌μs, so the time-triggered flow The optimal path is The link time slot allocation table is updated with the earliest transmission start time calculated by the optimal path. There are 3 paths to choose from: , and ,at this time , The cumulative link loads are 2, which is , , , , , as well as The maximum value of the load of these 7 links, so the time trigger flow There are two paths with the smallest link load, divided into and .because Compare Short length, As the transmission path, the earliest transmission start time is calculated first and it is found that it can be scheduled. The earliest transmission start time is 1 ‌ ‌μs, so the time-triggered flow The optimal path is The link time slot allocation table is updated with the earliest transmission start time calculated by the optimal path. In summary, after the scheduling of the four flows is completed, the network , , , The link load of is the highest, reaching 2, which is 50% lower than that of fixed routing. Figure 5 and Figure 6 The allocated time slots indicate that the time-triggered flow time slot allocation model based on joint routing scheduling and no-wait mode reduces the link The link load is reduced, that is, the peak value of the link load in the network is reduced.

[0030] Example 3 In this embodiment, the technical effect of the joint scheduling method of the present invention is verified and explained by comparing the joint scheduling method of the present invention with the other two methods.

[0031] In this embodiment, the two scheduling methods used for comparison with the method of the present invention are: (1) Shortest path scheduling method: Use the shortest path to replace the routing part of the method of the present invention.

[0032] (2) Equal-cost multi-path scheduling method: The routing part of the method of the present invention is replaced by the equal-cost multi-path method. The equal-cost multi-path method has one or more shortest paths according to different network topologies, and randomly selects one path during path selection.

[0033] The network topology scene diagram in this embodiment is as follows: Figure 7As shown in the figure, a mesh network topology consists of 10 time-sensitive network switches, each switch is connected to 1 terminal device.

[0034] Parameter setting: The link bandwidth is uniformly set to 1Gbps, and the time-sensitive network switch processing delay is set to zero. The time-triggered flow template shown in Table 1 is set in the flow set data generator and a variety of flow sets with different numbers [50, 500] are generated. Each flow set accounts for 33.33% of each flow. Each flow set contains 20 groups of scheduling tasks, and the average data is taken as the final result. All simulations are run on an Ubuntu 22.04 machine with an 8-core 3.6Ghz Intel Core i7-7700 CPU and 8GB of memory.

[0035] Table 1 Time-triggered flow template Link load peak reduction rate Figure 8 As shown, it can be seen that the routing and traffic joint scheduling method based on link load peak of the present invention can effectively reduce the link load peak in the network compared with the other two scheduling methods, and is reduced by 45.41% and 10.88% compared with the link load peak of the shortest path scheduling method and the equal-cost multi-path scheduling method, respectively.

[0036] The dispatch rate is Fig. 9 As shown, it can be seen that the routing and traffic joint scheduling method based on link load peak is superior to the other two scheduling methods in terms of schedulability, and its average scheduling rates are increased by 41.25% and 47.49% respectively compared with the shortest path scheduling method and the equal-cost multi-path scheduling method.

[0037] Execution time Fig.10 As shown, it can be seen that the execution time of the routing and traffic joint scheduling method based on link load peak is almost the same as that of the other two scheduling methods.

[0038] Example 4 Based on the method for joint scheduling of routing and traffic based on link load peak mentioned in Example 1, in this embodiment, a joint scheduling system for routing and traffic based on link load peak is proposed, which specifically includes: Flow set building module: Model the target network as a directed graph and define time-triggered flow sets; Time slot allocation model construction module: Based on the time-triggered flow set, combined with the idea of ​​load balancing, and in a way that frame forwarding does not allow queuing, from the perspective of traffic planning, a gated time slot allocation model for time-triggered traffic based on joint routing scheduling and frame forwarding without waiting is constructed; Scheduling problem building module: Establish the gating time slot allocation constraints of time-triggered traffic based on joint routing scheduling and frame forwarding without waiting, and based on the time slot allocation model, take minimizing the link load peak in the network as the scheduling goal to formalize the joint scheduling problem; And, a scheduling scheme determination module: based on the joint scheduling problem, calling a joint routing and joint scheduling algorithm based on link load peak value to determine a scheduling scheme for time-triggered traffic.

[0039] The method of the present invention may be implemented in hardware, firmware, or as software or computer code that may be stored in a recording medium (such as a CDROM, RAM, floppy disk, hard disk, or magneto-optical disk), or as computer code that is originally stored in a remote recording medium or a non-temporary machine-readable medium downloaded over a network and will be stored in a local recording medium, so that the method described herein may be stored in such software processing on a recording medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware (such as an ASIC or FPGA). It is understood that a computer, processor, microprocessor controller, or programmable hardware includes a storage component (e.g., RAM, ROM, flash memory, etc.) that can store or receive software or computer code, and when the software or computer code is accessed and executed by a computer, processor, or hardware, the method described herein is implemented. In addition, when a general-purpose computer accesses the code for implementing the method shown herein, the execution of the code converts the general-purpose computer into a dedicated computer for executing the method shown herein.

[0040] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A routing and traffic joint scheduling method based on link load peak, characterized in that: The following steps are involved: Model the target network as a directed graph and define a set of time-triggered flows; Based on the time-triggered flow set, combined with the idea of ​​load balancing, in a way that frame forwarding does not allow queuing, from the perspective of traffic planning, a gated time slot allocation model for time-triggered traffic based on joint routing scheduling and frame forwarding without waiting is constructed; Establish a gating time slot allocation constraint for time-triggered traffic based on joint routing scheduling and frame forwarding without waiting, and construct a joint scheduling problem based on the gating time slot allocation model with minimizing the link load peak in the network as the scheduling goal; Based on the joint scheduling problem, a joint routing and joint scheduling algorithm based on link load peak is called to determine a scheduling scheme for time-triggered traffic.

2. The method for joint scheduling of routing and traffic based on link load peak according to claim 1, characterized in that: The directed graph is ; Represents a collection of network nodes, consisting of a collection of terminal system nodes and switch node set composition; represents the set of links between adjacent network nodes, and Representation Node With Node A bidirectional link between The time-triggered flow set is , trigger flow at any time By , , , , , > Characterization, which represents the source node, destination node, size, cycle, generation time and deadline respectively.

3. The method for joint scheduling of routing and traffic based on link load peak according to claim 1, characterized in that: The gated time slot allocation model for time-triggered traffic based on joint routing scheduling and frame forwarding without waiting is: in, Represents a time-triggered flow The end-to-end delay of Indicates that the route is a time-triggered flow Select the transmission path, Represents a time-triggered flow The propagation delay of Represents a time-triggered flow The processing delay, Indicates the clock synchronization delay; Represents a time-triggered flow The transmission delay of represents bandwidth, Represents a time-triggered flow size.

4. The method for joint scheduling of routing and traffic based on link load peak according to claim 3 is characterized in that: The gating time slot allocation constraints of the time-triggered traffic based on the joint routing scheduling and frame forwarding no-wait mode include: frame constraints, frame transmission constraints, end-to-end constraints and link constraints; The frame constraints are: In the formula, express Any continuous link in express In the link The transmission start time on ; The frame transmission constraints are: in, represents the previous link in a continuous chain of links, represents the next link in the continuous link, express In the link The transmission start time on express In the link The transmission start time on ; The end-to-end constraints are: in, Represents a time-triggered flow Deadline: The link constraints are: in, represents a super cycle, Represents a time-triggered flow The index value of the number of transmissions in the super period, Represents a time-triggered flow The index value of the number of transmissions in the super period.

5. The method for joint scheduling of routing and traffic based on link load peak according to claim 4 is characterized in that: The joint scheduling problem is: in, Indicates the link load peak value, Indicates the link load, Represents a time-triggered flow In the link If the time-triggered flow Not passing , the value is 0.

6. The method for joint scheduling of routing and traffic based on link load peak according to claim 1, characterized in that: The steps of determining a time-triggered traffic scheduling scheme include: S401, input network topology , time-triggered flow set ; S402, defining a link time slot allocation table, a link load table, a transmission start time table, and a routing entry table, and the initial values ​​are all empty sets; S403, traversing time trigger flow set Each time-triggered stream in , use depth-first traversal to calculate the time trigger flow A collection of paths; S404, using the least common multiple method to calculate the time-triggered flow set The super cycle ; S405, time-triggered flow set The flows in are sorted in non-decreasing order according to the size of the supercycle; S406, traversing time trigger flow set Each time-triggered stream in , if the flow set traversal is completed, go to S416, otherwise go to S407; S407, traversal time trigger flow By comparing the link load peak of each path, find the path set with the smallest link load peak and sort them in non-decreasing order by path length; S408, traverse each path in the path set with the smallest link load peak value , if the path traversal is completed, go to S412, otherwise go to S409; S409, calculation time trigger flow In no-wait mode End-to-end delay as a transmission path ,if Trigger flow after time has passed Deadline , then enter S408 for the next cycle, otherwise enter S410; S410, calling the earliest transmission start time calculation algorithm to calculate the time trigger flow In no-wait mode The transmission start time when used as a transmission path ; If the earliest transmission start time is found, that is , then enter S411; otherwise enter S408 for the next cycle; S411, update time trigger flow The transfer start time and the optimal path , when one is found, the path traversal is terminated and the process goes to S412; S412, if the earliest transmission start time is found, that is , go to S413, otherwise go to S415; S413, updating the link time slot allocation table hop by hop and cycle by cycle, and reordering the allocated time slots on the affected links in ascending order according to the transmission start time, and updating the link load table at the same time, and entering S414; S414, update the transmission start schedule and routing entry table, and enter S406 for the next cycle; S415, clear the link time slot allocation table, the transmission start time table and the routing entry table, and enter S416; S416, returning the link time slot allocation table, the transmission start time table and the routing entry table.

7. A routing and traffic joint scheduling system based on link load peak, characterized in that: include: Flow set building module: Model the target network as a directed graph and define time-triggered flow sets; Time slot allocation model construction module: Based on the time-triggered flow set, combined with the idea of ​​load balancing, and in a way that frame forwarding does not allow queuing, from the perspective of traffic planning, a gated time slot allocation model for time-triggered traffic based on joint routing scheduling and frame forwarding without waiting is constructed; Scheduling problem construction module: establishes the gating time slot allocation constraints of time-triggered traffic based on joint routing scheduling and frame forwarding without waiting, and constructs the joint scheduling problem based on the gating time slot allocation model with minimizing the link load peak in the network as the scheduling goal; And, a scheduling scheme determination module: based on the joint scheduling problem, calling a joint routing and joint scheduling algorithm based on link load peak value to determine a scheduling scheme for time-triggered traffic.

8. A computer storage medium storing a readable program, characterized in that: When the program is running, it can execute the routing and traffic joint scheduling method based on link load peak value described in any one of claims 1 to 6.

9. An electronic device, characterized in that: include: A processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other via the communication bus; The memory is used to store at least one executable instruction, and the executable instruction enables the processor to perform operations corresponding to the routing and traffic joint scheduling method based on link load peak according to any one of claims 1-6.

10. A computer program product comprising computer instructions, characterized in that: The computer instructions instruct the computing device to perform operations corresponding to the routing and traffic joint scheduling method based on link load peak as described in any one of claims 1-6.

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